For LEDs, we had a patch series floating around adding LED triggers [1],
and it seems to me like the LEDs class subsystem would be a good fit for
controlling PHY LEDs, possibly with the help of PHYLIB when it comes to
doing the low-level work of registering LEDs and their names with the
LEDS subsystem.
[1]: http://lists.openwall.net/netdev/2016/03/23/61
That patch fizzled out. I got the feeling it was pushing the
capabilities of the coder. I do however think it is a reasonable path
to follow for PHY LEDs.
I took a quick look at the datasheet and the controlling of the LEDs
is very flexible. It should not be a problem to expose some of that
functionality via LED triggers.
Andrew